Gas turbine combustor with controlled fuel mixing

Claim 2

A combustor, comprising, in combination: an outer casing; a flame tube disposed within said casing and spaced apart therefrom to form an annular chamber between said flame tube and said casing; a plurality of fins extending from the external surface of said flame tube into said annular chamber; inlet means for introducing a swirling stream of air flowing in a downstream direction into the upstream end portion of said flame tube as the sole stream of air introduced into said upstream end portion of said flame tube; and fuel inlet means for forming a sole annular stratum of fuel around said stream of air flowing into said flame tube by introducing said fuel in a direction toward and which is from tangential to less than perpendicular, but non-parallel, to the periphery of said stream of air to effect controlled mixing of said fuel and air at the interface therebetween and produce a sole annular fuel-air mixture for introduction into said upstream end portion of said flame tube.

Claim 3

A combustor according to claim 1 wherein said fuel inlet means is adapted to introduce said fuel in a direction which is intermediate tangent and perpendicular to the periphery of said stream of air.

Claim 4

A combustor according to claim 1, comprising, in further combination, means positioned downstream from said air inlet means and said fuel inlet means for causing uniform and graduated expansion of said air and said fuel during entry thereof into said flame tube.

Claim 5

A combustor according to claim 1 wherein said air inlet means comprises a swirl chamber disposed at the upstream end of said flame tube, and having a diameter less than the diameter of said flame tube; and conduit means for introducing a swirling mass of air into the upstream end portion of said swirl chamber.

Claim 6

A combustor according to claim 4 wherein said conduit means comprises a plurality of air conduits extending into said swirl chamber tangentially with respect to the inner wall thereof.

Claim 7

A combustor according to claim 1 wherein: a closure member is provided for closing the upstream end of said flame tube; and said air inlet means comprises a conduit extending through said closure member into communication with the upstream end portion of said flame, and at least one swirl vane positioned in said conduit.

Claim 8

A combustor according to claim 6 wherein: a recess is formed in the downstream end portion of said closure member; and said fuel inlet means comprises a plurality of fuel conduits extending into said recess tangentially with respect to the wall thereof.

Claim 9

A combustor according to claim 6 wherein said closure member comprises: an upstream element having said conduit formed therein; a downstream element having formed therein an expansion passageway which flares outwardly from a point adjacent the downstream end of said conduit to the inner wall of said flame tube; an inner wall of said downstream element is spaced apart from and is complementary in shape to the downstream end wall of said upstream element so as to form a fuel passageway between said inner wall of said downstream element and the downstream end wall of said upstream element; and said fuel passageway communicates with and forms a part of said fuel inlet means.

Claim 10

A combustor according to claim 8, and further comprising means for varying the width of said fuel passageway formed between said upstream and downstream elements of said closure member.

Claim 11

A combustor comprising, in combination: a flame tube, open at its downstream end; a closure member closing the upstream end of said flame tube; an outer casing disposed around said flame tube and said closure member and spaced apart therefrom to form an annular chamber around said flame tube and said closure member, said annular chamber being closed at its downstream end; a plurality of fins extending from the external surface of said flame tube into said annular chamber; a generally cylindrical swirl chamber formed in said closure member, the downstream end of said swirl chamber being in open communication with the upstream end of said flame tube; a first air inlet means for introducing a swirling mass of air into the upstream end portion of said swirl chamber and then into the upstream end of said flame tube as the sole stream of air introduced into said upstream end of said flame tube; and fuel inlet means for forming a sole annular stratum of fuel around said stream of air flowing in a downstream direction from said swirl chamber into said flame tube by introducing said fuel in a direction toward and which is from tangential to less than perpendicular, but non-parallel, to the periphery of said stream of air to effect controlled mixing of said fuel and air at the interface therebetween and produce a sole annular fuel-air mixture for introduction into said upstream end portion of said flame tube.

Claim 12

A combustor comprising, in combination: a flame tube, open at its downstream end; a closure member closing the upstream end of said flame tube; an outer casing disposed around said flame tube and said closure member and spaced apart therefrom to form an annular chamber around said flame tube and said closure member, said annular chamber being closed at its downstream end; a plurality of fins extending from the external surface of said flame tube into said annular chamber; a generally cylindrical swirl chamber formed in said closure member, the downstream end of said swirl chamber being in open communication with the upstream end of said flame tube; a first air inlet means for introducing a swirling mass of air into the upstream end portion of said swirl chamber and then into the upstream end of said flame tube as the sole stream of air introduced into said upstream end of said flame tube; and fuel inlet means for forming a sole annular stratum of fuel around said stream of air flowing in a downstream direction from said swirl chamber into said flame tube by introducing said fuel in a direction toward and which is from tangential to less than perpendicular, but non-parallel, to the periphery of said stream of air to effect controlled mixing of said fuel and air at the interface therebetween and produce a sole annular fuel-air mixture for introduction into said upstream end portion of said flame tube.

Claim 13

A combustor according to claim 10 wherein: a first plurality of openings is provided in said flame tube downstream from said closure member for admitting a second stream of air into said flame tube from said annular chamber; and said fins are provided on said flame tube in the region between the downstream end portion of said closure member and said first plurality of openings.

Claim 14

A combustor according to claim 11 wherein a second plurality of openings is provided in said flame tube, downstream and spaced apart from said first plurality of openings for admitting a third stream of air into the interior of said flame tube from said annular chamber.

Claim 15

A combustor according to claim 12 wherein the downstream end portion of said closure member comprises an expansion formed therein and which flares outwardly from a point adjacent the downstream end of said swirl chamber to the inner wall of said flame tube.

Claim 16

A combustor according to claim 13 wherein said closure member comprises: an upstream element having said swirl chamber formed therein; a downstream element having said expansion passageway formed therein; an inner upstream end wall of said downstream element is spaced apart from and is complementary in shape to the downstream end wall of said upstream element so as to form a fuel passageway between said inner wall of said downstream element and the downstream end wall of said upstream element; and said fuel passageway communicates with and forms a part of said fuel inlet means.

Claim 17

A combustor according to claim 14 and further comprising means for varying the width of said fuel passageway formed between said upstream and downstream elements of said closure member.

Claim 18

A combustor according to claim 10 wherein said fuel inlet means comprises a plurality of conduits extending tangentially through the downstream end portion of said closure member adjacent the downstream end of said swirl chamber.

Claim 19

A combustor according to claim 16 wherein: said air inlet means comprises a plurality of air conduits extending into said swirl chamber adjacent the upstream end portion thereof and tangentially with respect to the inner wall thereof; a recess is formed in the downstream end portion of said closure member; and said fuel inlet means comprises a plurality of fuel conduits extending into said recess tangentially with respect to the wall thereof.

Claim 20

A combustor according to claim 17 wherein said air conduits extend tangentially into said swirl chamber in one of a clockwise manner and a counterclockwise manner, and said fuel conduits extend tangentially into said recess in the other of said clockwise and said counterclockwise manner.